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Zheng et al. Soft Sci. 2026, 6, 32 Page 27 of 57

fibers showed good fast charge/discharge capability and structural stability, with a capacitance retention of
81.4% when the scan rate rose from 5 to 1,000 mV·s [Figure 9M] .
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Thermal properties
MXene’s optical characteristics are highly tunable, and the chemical makeup and spatial distribution of its
surface end groups largely control its electronic structure and optical response . In addition to affecting the
[129]
material’s bandgap structure and energy level arrangement, these functional groups also directly affect how
light is absorbed, reflected, and transmitted across the ultraviolet to near-infrared spectrum. For example,
because of strong surface polarization effects, MXene rich in -F and -OH functional groups usually shows
low optical absorption coefficients in the visible area. On the other hand, MXene systems that have been
altered with different end groups might show improved light-trapping effectiveness. The selective scattering
mechanism of end groups toward high-energy photons is the main reason why adding surface functional
groups can greatly increase material reflectivity in the ultraviolet (UV) spectrum. The interlayer structure of
MXene has a significant impact on its optical characteristics in addition to surface chemical control. Light
propagation paths between layers can be efficiently controlled by varying the interlayer gap using
intercalants. The total transmittance and absorption properties of the material can be systematically
controlled by increasing the interlayer distance, which improves multiple reflections and scattering. For
MXene optical design, this structural tailoring in conjunction with surface chemical alteration offers a
multifaceted optimization approach.

MXene’s excellent photothermal conversion capabilities are directly attributed to its exceptional and tunable
optical characteristics. Through non-radiative relaxation processes, MXene effectively transforms light
energy into heat after absorbing photons. This feature shows enormous potential for MXene-based fibers
and fabrics in heat management applications for smart textiles, together with its intrinsic high electrical
conductivity and processability. As seen in Figure 10A, the MXene/cellulose nonwoven created by Zhao et al.
quickly warms to 100 °C at low voltages (3-6 V), allowing for regulated thermotherapy [Figure 10B] and
antibacterial effects while retaining stability after thousands of flexures [130] . Additionally, biomimetic
structural design improves functional integration. For example, Wang et al. created MXene/ANF composite
paper inspired by pearl layers, which combines high mechanical strength, effective electromagnetic shielding,
and quick Joule heating response . As seen in Figure 10C, the temperature consistently increases to 146 °C
[131]
at 4 V, which makes it appropriate for integrated electromagnetic shielding wearable systems and
high-performance thermal management fabrics. Furthermore, self-healing functionality is made possible by
the photothermal characteristics of MXene. In order to create a self-healing heater, Choi et al. coated
polycaprolactone (PCL) fiber surfaces with MXene and AgNWs . As seen in Figure 10D, the material was
[132]
heated to 61 °C by delivering a 1.6 V voltage upon injury, melting the PCL and enabling autonomous
healing.

Chang et al. used electrospinning to create MXene/cellulose smart textiles for photothermal synergistic
applications [133] . Figure 10E and F display their temperature-time curves and UV-Vis-near-infrared (NIR)
absorption spectra under single-sun irradiation. These materials demonstrated dual functionality for
solar-driven water treatment and personal thermal control, rising 5.6 °C more than cotton garments under
outdoor sunlight [Figure 10G] while exhibiting effective water evaporation rates. Additionally, MXene’s
strong near-infrared absorption creates opportunities for uses in biomedical and specialty textiles, including
infrared stealth and photothermal therapy [137-139] .

Other performance
In addition to their remarkable conductivity, MXene materials’ distinct surface chemistry gives them
superior solvent dispersibility and processing compatibility, providing a vital basis for their use in a variety of